method and system for generating and displaying an interactive dynamic culling graph view of multiply connected objects

ABSTRACT

A method and system for generating a graph view on a user interface in a computing environment, is provided. One implementation involves, at a server, generating coordinate data for a graph representing multiply connected objects; transmitting the coordinate data to a client as lightweight object data; and at the client, based on the lightweight object data rendering an interactive dynamic graph view on a user interface; wherein the rendered graph view includes representations of a plurality of the multiply connected objects selected by depth culling the graph according to graph depth display control information.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates generally to graphical display of data, and in particular, to displaying a graph view of multiply connected objects.

2. Background Information

Visualization of and interaction with data helps users quickly understand the types of data available and their interrelationships. Often, sets of data are presented as lists, or tables with columns, depicting specific attributes of each instance of data. Analyzing and understanding the nature and state of units of data, and appreciating any subtle relationships and connections therebetween, can be difficult and time consuming. For example, in a screen display, large sets of textual data cannot fit on a single display without the user having to scroll or page, whereby a user cannot retain a view of all the data at once.

A conventional solution is to draw a graph of objects with lines indicating relationships between pairs of objects, and some arbitrary shape representing each instance of an object. Typically, the scale of the graph can be controlled, and the data arranged in such a way that all data or a selection of data can be viewed in a single screen. An example of this is a unified modeling language (UML) editor, which allows users to examine a set of object classes and the relationships between them. The user can move around the graph, zoom into items of interest and view details of specific classes (e.g., zoom into objects in the graph and identify relationships that exist between classes).

In a complex graph, where there a multiple objects with connections to many other objects, the end result can be a tangled graph, which is difficult to make sense of Graph drawing techniques and algorithms are well known and attempt to reduce this visual complexity by arranging the objects in an aesthetically pleasing layout, such as a hierarchy, or by evenly distributing the objects within the extent of the display. Another technique to improve clarity of a graph is to move objects around such that the number of crossings of connection lines is minimized. These require redrawing the graph at a server as a bitmap, transmitting the bitmap to a client via communication link, and displaying the bitmap at a client. However, this consumes communication bandwidth and is slow.

In a client rendering environment, the number of objects to draw is typically a limiting factor, where either the time to send the graph data is unacceptable, or the graph drawing capabilities of the client are insufficient for the number of objects to show. The number of objects depends on the data set being considered, the number of connections between objects, and the depth of the graph that is being requested. For example, in a tree view (a directed hierarchical graph), an origin object may connect to 5 objects at the first level, then each of those connects to 5 objects each at the second level, and the number of objects grows exponentially. Computing a layout for a large graph is time consuming and may exceed the capabilities of the client.

SUMMARY OF THE INVENTION

The invention provides a method and system for generating a graph view on a user interface in a computing environment. One embodiment includes, at a server, generating coordinate data for a graph representing multiply connected objects; transmitting the coordinate data to a client as lightweight object data; and at the client, based on the lightweight object data rendering an interactive dynamic graph view on a user interface; wherein the rendered graph view includes representations of a plurality of the multiply connected objects selected by depth culling the graph according to graph depth display control information.

The graph depth display control information may include a threshold for controlling the amount of graph data sent to a client form the server. The graph view may include visual elements connected by edges, such that the visual elements represent the objects and the edges represent relationships between the objects, and the graph depth display control information includes a threshold for controlling the amount of graph data sent to a client form the server. The process further includes examining relationships in the graph of objects and counting the number of objects added to the graph, such that when the number of objects reaches said threshold, no additional objects are added to the graph.

The process may further include detecting objects that have connections to other objects beyond said threshold, and representing said objects beyond said threshold by a specialized representation indicating a graph truncation. The process may further include, upon receiving user selection of a specialized representation, requesting additional graph data from the server and rendering the additional graph data at the client.

The graph depth control information may include: unlimited depth, wherein the server traverses all the relationships in the hierarchy of objects starting at a root object until there are no more relationships to follow; or automatic depth, wherein the server performs a breadth-first traversal of the object graph data, retrieving objects until the number of objects reaches a threshold.

The computing environment may comprise a service-oriented architecture and the data source comprises a service registry, the client may comprise a web browser on a thin client computing module, the server may comprise a server application on a server computing module, wherein the client module and the server module may be connected via a communication link.

These and other features, aspects and advantages of the invention will become understood with reference to the following description, appended claims and accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the nature and advantages of the invention, as well as a preferred mode of use, reference should be made to the following detailed description read in conjunction with the accompanying drawings, in which:

FIG. 1 shows a functional block diagram of a system for generating and displaying an interactive dynamic graph view of multiply connected objects, based on a culling of the graph, according to an embodiment of the invention.

FIG. 2 shows a flowchart of a process for generating and displaying an interactive dynamic graph view of multiply connected objects, based on a culling of the graph, according to an embodiment of the invention.

FIGS. 3-12 show examples of generating and interacting with a graph view, according to embodiments of the invention.

FIGS. 13-16 show examples of generating and interacting with a graph view based on a culling of the graph, according to embodiments of the invention.

FIG. 17 shows a functional block diagram of an example computing environment implementing an embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description is made for the purpose of illustrating the general principles of the invention and is not meant to limit the inventive concepts claimed herein. Further, particular features described herein can be used in combination with other described features in each of the various possible combinations and permutations. Unless otherwise specifically defined herein, all terms are to be given their broadest possible interpretation including meanings implied from the specification as well as meanings understood by those skilled in the art and/or as defined in dictionaries, treatises, etc.

The invention provides a method and system for generating and displaying an interactive dynamic graph view of multiply connected objects. One embodiment involves controlling the amount of information sent to a client rendering module, such as web browser, when initially the size of a connected graph is unknown. This reduces the demands on a browser client to draw a graph with a large number of objects, and at the same time indicates to the user where more connections exist and can be retrieved. Further, the invention eliminates the need for sending an entire graph to the client to be rendered, thereby reducing the overall communication link (network burden).

One embodiment involves generating graph data representing multiply connected objects at a server module, transmitting the graph data from the server module to a client module (such as web browser client) via a communication link, and then at the client module displaying an interactive dynamic graph view of the objects. The graph view content includes visual representations of the objects and object relationships, and may further include information about objects types and relationship types. The graph content is dynamically rendered. The graph content may be selectively displayed based on control information such as filtering based on object and/or relation types, etc.

The invention limits the level of complexity of the rendered graph to a threshold (pre-set level) which may be user-controlled for a client graph rendering function or applied in a server graph creation function. As such, the threshold may be enforced at the client, the server, or both. As the relationships in the graph of objects are examined and the optimized coordinates of those objects is calculated using standard graph drawing algorithms and techniques, the number of objects added to the graph is counted. When the number of objects reaches a threshold, no additional objects are added to the graph. The objects that have connections to other objects that will not be present in the final graph are connected to a dummy object or node that indicates where a graph truncation occurs. This reduced graph layout is sent by the server module to the client module as graph coordinate data, to be rendered visually by the client as a graph view on a user interface. If the user selects a dummy object or node that indicates there is more data originating from the object attached to the dummy node, the client can request that the additional graph data be retrieved from the server module.

A preferred implementation of the invention is in relation to registry applications, described below. A registry application manages sets of data that can be multiply inter-connected by any number of relationships, where each data object may represent some physical artifact or business unit. Users of such a registry are interested in understanding the inter-dependencies between the objects stored in the registry, such that they can quickly see the effect of changing any of the data objects on other data. It is also a convenient way of applying a common operation to multiple objects selected in the graph representation.

In the description below first an example of generating and presenting a graph view to the user is described. Then an example of reducing the graph size by depth culling of the graph to reduce graph view complexity and network load between the client and server modules, is described.

Generating Graph View

An example rendering system generates and displays an interactive dynamic graph view of multiply connected objects. The rendering system implements a rendering process for generating a dynamic graph view for illustrating, and interacting with, multiply connected objects in a web browser client. The rendering process allows a user to interact with the graph to find more information about the objects displayed or perform further actions with one or more of the objects. The system allows display of a graphical view to an end user with commonly available web browsers without the need to install plug-ins.

The system uses the capabilities of browsers and software libraries to enable data generated by server applications to be visualized as vectors that can be scaled, transformed and interacted with using vector graphics, providing users with similar quality presentation as dedicated rich client applications combined with the network efficiencies of a thin client retrieving pre-processed data from a server application. In addition, the system provides a mini-portal view of the entire graph allowing the user to track location regardless of the current scale factor of the graph. The system also provides a history of previous graph views so the user can return to previous views easily, without requiring much storage on the client and none on the server (this addresses a common problem with asynchronous browser applications where the user presses the back button to go to a previous view and then finds they are no longer on the same page).

A graph of objects is stored and managed by an application running on a server machine (i.e., server application executing on a computing device or system). The objects may or may not be interconnected. The objects have properties that allow them to be differentiated. For example, they may have a property that indicates the type of the object, or a name property that provides a human readable label. Objects may be connected to one another by relationships. A relationship originates from a source object and connects to a target object. The relationship itself may have properties to track which source and target objects it spans, and also descriptive properties such as a relationship name.

In order to view the graph of objects in a user interface, a set of relative coordinates for shapes that represent each of the objects in the graph is computed by the server application, such that the visible graph represents the structure of the graph (i.e., the objects that make up the graph and the relationships between them). This calculation may also apply constraints to improve the “readability” of the drawn graph. The constraints that affect structural and aesthetic interpretation may include: connection lines that represent relationships, should not cross; connection lines should not cross shapes that represent objects; any hierarchy in the graph should be apparent, either by position or by indicating direction of relationship; connection lines should be short; connection lines should be aligned straight (e.g., horizontal or vertical); the distance between two objects should be as short as possible.

Once the graph layout (i.e., the set of graph coordinates assigned to objects and relationships) is determined, the graph can be drawn on a user interface by the server application. For an environment where a web browser provides the user interface, the server application must make this graph coordinate data available via a HTTP request. The graph may be transformed into a bitmap image (such as a JPG or GIF format file) and displayed on the web page. The image is static and provided limited interactivity. Each bitmap image consumes storage and network bandwidth, depending on the color depth and quality of the image. Specifically, the graph could be drawn as a bitmap image by the server but that is inefficient as it causes large network load, and is not interactive. It is therefore preferably to send only the coordinates to the client wherein the client renders the graph such that users can interact with the individual elements of the graph.

Asynchronous JavaScript and XML (AJAX) describes a technology that is used to retrieve data to a client, such as a web browser for drawing graphs (no special client side code/plug-ins are required). AJAX describes a technology (i.e., a combination of technologies) where web browser clients make an asynchronous HTTP request to a server and when data is returned as Extensible Markup Language (XML) or JavaScript Object Notation (JSON), it activates an event in a JavaScript program executed within the browser. JavaScript code can be written to handle these events, and modify the current HTML page in place in some way that reflects only changes to the page rather than redrawing the entire web page.

According to an embodiment of the rendering system, history lists are used in conjunction with graph rendering and AJAX to allow previous graphs to be redrawn. Overview windows are applied to the graphs. One implementation is for accessing the data in a service registry and displaying the data in a web browser environment for a service-oriented architecture (SOA) computing environment. In a SOA environment, Service Registries contain documents that relate to services and the associated schemas, policies, etc.

One implementation using AJAX provides a lightweight system for graphic illustration of server content, in a system agnostic manner (client) while maintaining fluidic interaction. The system summarizes content as concise elements, until focus is attained and sustained on an element for illustrating full element content. The system preserves navigation context, so as to be able to return to previously visited areas of focus in a model. The system displays content of a greater volume by using a scrollable, visual overview window.

An AJAX implementation of a rendering system for drawing objects in a browser environment is described below. A graph settings data structure is utilized by the rendering system, which allows the client and server implementations to control the parameters which affect how the object graph is retrieved and presented. This includes filtering the types of objects to be shown in the graph, the types of relationships to show, the orientation of the graph (left to right or top to bottom), etc. FIG. 1 shows a functional block diagram of a rendering system 10, according to the invention. The system 10 includes a client including a browser client 12, and a server 13 including a server application 14 which accesses data objects from a data source 15 (e.g., database such as a SOA service registry). At the request of the browser client 12, the server application 14 generates graphs from said objects in the data source 15, to be displayed by the browser client 12. The client 12 has a display and user input devices, and may be a computing module, a computing node, a computing device, etc. The server 14 may be, for example, a computing module, a computing node, a computing device, computing system, etc. The client and the server are connected via a communication link (e.g., network, Internet) for data communication. The server may service multiple clients according to an embodiment of the invention.

Referring now also to FIG. 2, the rendering system 10 implements a process 20, according to an embodiment of the invention, including the process blocks described below.

Block 21: The client (e.g., browser client) requests a graph view from the server application.

Block 22: The server application accesses a data source for data to be presented as a graph, and computes graph coordinates and layout. The server application may comprise a distributed server application. The data source may comprise a database or a service registry in an SOA. The server application sends the graph coordinate data to the browser client in a lightweight, standard format.

Block 23: The browser client includes event handling code to process graph coordinate data into a form suitable for display. The browser client further includes rendering code for a graph drawing function library that allows vector graphics to be drawn to any browser that supports a vector drawing format, such as Scalable Vector Graphics (SVG) or Vector Markup Language (VML). The browser client code is not dependent on any specific implementation of vector drawing capabilities in the browser, either built-in or by installed plug-in. The graph is rendered at the browser client using vector graphics.

Block 24: The browser client code processes the received graph coordinate data by drawing shapes (e.g., rectangles) where an object in the graph is to appear, connects those shapes together where a relationship exists and indicates direction with an arrow head. The browser client code then appends labels on objects and relationships where such properties have been provided by the server application. The graph coordinates are scaled to fit in the available graph drawing area, or to match the scale factor requested by a user.

Block 25: The browser client code then determines when the mouse cursor (e.g., moved by the user) is over any shape or connection in the graph and may provide additional visual cues (e.g., highlighting shapes and connections in a different color or style, or showing additional information about an object).

Block 26: The browser client code determines when the user “clicks” an object by moving the mouse cursor over the object and clicking the mouse button. This action results in a behavior determined by the application programmer (e.g., selection of the object or objects, ready for some other action to be chosen and applied, etc.).

Block 27: The browser client code allows the drawing canvas to be “dragged” around the visible drawing area such that the graph contents are moved correspondingly. The user moves the mouse cursor to an area where no objects have been drawn and holds down the mouse button while moving the mouse cursor. This has the effect of attaching the cursor to the drawing area and as the mouse is moved, the graph contents move correspondingly.

Block 28: The browser client code identifies (e.g., highlights) the object from which the graph drawing originates, the root object (e.g., by drawing its outline rectangle in a solid blue line). The browser client code allows selection for display of additional information. In one implementation, the browser client allows selection of objects by clicking within the shape being used to represent the object. Selection of an object is indicated by e.g., shading the object shape a different color. This indication allows the user to choose and apply an action to the currently selected objects. Further, the browser client code can provide additional information about any graph element (such as an object or a relationship) when the user hovers the mouse cursor over the element. This highlights the object under the cursor (e.g., with a yellow dotted outline) and displays a pop-up window or tooltip containing the additional information.

The above process is now described in further detail in terms of the operations of the server and the client.

When the server application receives a request from the client to generate graph coordinates and other information for a graph of a given depth starting from a specified origin (root) object having an identification ID, a graph creation function 18 (FIG. 1) of the server application discovers and maintains relationships for display as a graph.

Starting with the root object ID, the object is retrieved from the data source 15 by the graph creation function 18. The graph creation function 18 then creates a graph node with properties that are required for display (e.g., object name, type, unique ID). The graph node is added to a map of node IDs. The graph node is set as the source node (source object).

Next, the graph creation function 18 recursively traverses relationships from that object to find the next level of target objects to add to the graph, according to the settings for the graph passed from the client. The settings determine the depth of objects to be fetched and the types of relationship to be followed. Next, when a relationship is traversed, the graph creation function 18 retrieves the target objects, wherein if the object ID for a target object does not exist in the node map, a graph node is created with properties required for display of the target object (as for the source node), plus a unique ID. If the graph node does already exist, it is retrieved from the node map.

The graph creation function 18 then adds the graph nodes to an edge object. An edge object represents one or more relationships between the source object and the target object. Importantly, an edge can represent more than one relationship. It does so via a relationship vector object for each type of relationship connecting the source object and target object.

After an edge is created between source and target graph nodes, the graph creation function 18 sets the target nodes as source nodes in turn and their relationships traverse until the depth limit set by the graph settings object is reached. At this point, there is a set of graph node objects and a set of graph edges. This collection of data is then provided to a graph processing function 19 (FIG. 1) of the server application to transform the collection data into a set of graph objects with coordinates such that the graph meets readability constraints (i.e., the graph contents are arranged such that the connection crossings are minimized and connection lengths are reduced to reduce graph density and complexity). If relationships exist that may cause a cycle in the graph, these relationships are reversed and marked as such. This allows the entire graph to have all relationships in the forward direction (i.e., the graph flows away from the root object). This helps the layout engine arrange the objects in the graph in a hierarchical manner.

The graph processing function 19 then transforms the graph data objects into lightweight objects that can be transferred to the client 12 efficiently across the communication link. In one example, the “lightweight objects” comprise the minimal representations of objects required by a client application to render a graph and are optimized and arranged such that the client can process them quickly. When the server application processes related objects to build up the graph structure, there are several properties on those objects that are only relevant in the server application context (sending these to the client consumes valuable network and memory resources). The server application typically runs on a dedicated, high performance machine and preparing the data for transmission to the client relieves the client of having to do any object unpacking and transformation, and has little effect on the performance of the server application. The role of the client application is to render the graph coordinates and respond to user input. The object graph classes are designed to avoid any duplication of data, to keep identifier strings small, and also provide mappings between related objects to assist processing of the data at the client 12. Object attributes are described only once. An edge list references the objects by ID. All object types are reduced to a unique object type ID. All relationships are reduced to a unique relationship ID. Cyclical references are avoided using data structures that deliberately separate the list of object nodes and the list of relationships between those nodes. A separate data structure provides access to the natural language support (NLS) translated text (in the client) for the names of each of the types of object and the names of each of the relationships.

The object graph is serialized (e.g., in JavaScript Object Notation (JSON) format) and sent to the client 12 from the server application 14. In one example, using JSON reduces the amount of data sent from the server to client compared with XML, and clients using JavaScript not need parse the data from XML elements (they are transformed into JavaScript objects on arrival at the client by the browser).

At the client 12, the client code comprising a graph processing function 17 receives the received object graph data. A rendering function 16 of the client code then scales the coordinates of objects to match the display area, renders visual elements such as shapes/icons, to represent graph objects, and adds text properties. Relationships between objects are drawn as connecting lines (edges) between the shapes. When processing relationships, the rendering function inspects the relationship vectors and if they are marked as reversed, it switches the direction and draws an arrowhead in the correct direction.

The rendering function inspects each edge object and the relationship vectors associated with them. If there is more than one relationship vector in the same direction, the rendering function draws a double arrowhead, or a single arrow if there is a single relationship vector. If the relationship vector is marked as reversed, the connection line can have an arrowhead pointing in the other direction, or a separate connection drawn with a reverse pointing arrowhead.

To set up mouse event handling code when a user moves a mouse cursor over a relationship connection line, the client stores a reference ID in an attribute on the HTML element used to represent the connection line. When a mouse-over event occurs, the client can retrieve the edge data that the connection represents in order to build the list of information to display in the pop-up window or tooltip. For each relationship vector in the edge object, the client code can use the relationship ID to look up a text label for that relationship (e.g., in the locale suitable for a client web browser).

An example operation scenario of the rendering system 10 according to the above process 20 is described below.

Requesting a Graph for a Starting Object

The server application 14 provides the browser client 12 with a list of data objects from the data source 15. This list can be a predefined list of objects of the same type or the result of a search of objects that match some criteria. The user selects an object from the list, requesting a graph to be drawn. Specifically, the user selects an object (i.e., root object) from the list of available objects, requesting that a graph be drawn for the selected object. FIG. 3 shows an example of a user interface for list 30 of objects 31 from a service registry, wherein the user may request generating a graph for the object by selecting a graph icon 31 i (e.g., WSDL document object) from the list 30. The user interface is displayed by the browser client. The user may be viewing a detail view of an object 31 selected from the list 30, and then requests drawing a graph for it. FIG. 4 shows an example detail view 40 for a selected WSDL document object 31 displayed by the browser client 12, wherein a user is clicking a Graphical View link 32 therein to request a graph generation process for the object 31.

When the browser client 12 request drawing a graph based on the current object, an asynchronous HTTP request is made from the browser client 12 to the web server application 14 via the communication link. The server application 14 begins processing the graph, and in the meantime the browser client 12 may, for example, display an animated icon to indicate the request is being processed.

When the server application 14 completes generating the graph, it sends the graph data to the browser client 12 as XML or some other text format, and the rendering function 16 (FIG. 1) of the browser client 12 is notified accordingly. The rendering function 16 then parses the received graph data and renders a graph of the root object 31, wherein the graph includes graph elements (shapes) and connections. FIG. 5 shows an example graph 45 in a window display 41 of the browser client, including shapes 46 that represent objects 35 and lines/arrows 47 that represent connections (relationships). In the following, example operational features of the rendering function 16 are described.

Object and Relationship Highlighting and Information Views

In the graph 45, by default, the root object 31 (e.g., Address.wsdl WSDL Document) is highlighted (e.g., in a different color) relative to other data objects 35 corresponding to the root object 31. In the example graph 45 (FIG. 5), all objects 31, 35, are shown as rectangles, with a text label showing the object name value. Differences between object types are indicated by a graphical icon and a text label displaying the object type. Objects are further differentiated by whether they are physical documents (e.g., as a rectangle with a solid outline, such as object 31) or objects derived from the contents of those documents (e.g., as rectangles with dotted outlines, such as objects 35). Relationships between objects 31, 35, are shown as lines 47 with arrowheads indicating the direction of the relationship.

Referring to FIG. 6, an example view 50 of the graph 45 is shown. Hovering the mouse cursor 51 over a connection 47 highlights that connection (e.g., in a different color or style) and displays a pop-up window (or tooltip) 52 that includes the name (e.g., SOAPAddress) for the relationship(s). This saves the graph view from being cluttered with unnecessary labels. Highlighting the connection helps the user identify which relationship the window 52 is referring to, which is especially useful when the graph is complex with many, possibly intersecting connections 47. Referring to FIG. 7, similarly, hovering the mouse cursor 51 over a shape 46 representing an object, highlights the shape 46 (e.g., in a different color and/or style) and displays a pop-up window (or tooltip) 53 providing further details about the object. This saves the graph view from being cluttered with unnecessary information and labels.

Object Selection and Applying Actions

Objects in the graph 45 can be selected by clicking on their representative shapes 46. As shown by example in FIG. 8, one or more selected objects are shows by highlighted shapes 46 s. To select more than one graph object, a control key can be held down as the user clicks on each of the objects they wish to add to the selection. With multiple objects selected, actions can be performed on all of the selected objects simultaneously by choosing the action from e.g. a pop-up list 56. In one example, certain actions may not be applicable when multiple objects in the graph are selected or when certain types of object are selected (e.g., inapplicable actions are disabled and grayed out in the list 56).

Navigation Context with Scrollbars, Canvas Dragging and Viewport

As shown by example view 60 in FIG. 9, if the extent of the graph 45 is beyond the area of a main graphical view window 41 of the browser client, then one or more scrollbars 61 are displayed. The user can move to other, hidden, areas of the graph by moving the scrollbars in the appropriate direction. In addition to using scroll bars to move around the extent of the graph, the rendering function provides the ability to drag the background drawing canvas. That is, the user can place the mouse cursor on an empty area of the display, press a mouse button and drag the graph 45 around to the desired position within a graphical view window 42. The user can control movement in the horizontal and vertical directions simultaneously. When the user is dragging the canvas, the mouse cursor changes to indicate the dragging mode. In the example shown in FIG. 9, the canvas has been dragged to the right.

In the preferred embodiment, the rendering function implements a viewing window 62 onto the graph, to help users navigate around the graph, particularly when the graph does not fit the available display area. The example viewing window 62 represents a compact, simplified view of the entire graph structure 63, without text labels or connections. A view port window 64 (e.g., semi-transparent rectangle) within the viewing window 62 may be controlled by the user and can be dragged around in the viewing window 62 over the compact representation of the graph. Whatever underlying objects in the viewing window 62 are within the boundary of the view port 64, are displayed in the graphical view window 42 in more detail (the viewing window 62 is synchronized to the graphical view window 42). Referring to the example view 65 in FIG. 10, as the view port 64 is moved, the displayed portion of the graph 45 in the graphical view window 42 changes correspondingly.

In this example, the proportions of the view port rectangle 64 match the relative proportions of the graphical view window 42. If the graphical view window 42 is wider than it is in the vertical dimension, this is reflected in the view port rectangle 64 of the viewing window 62. The size of the viewing window 62 is fixed and represents the contents of the entire contents (objects) graph structure 63. If the graphical view window 42 is sufficiently large to display all objects in the graph structure 63, the view port control 64 extends to the same size as the viewing window 62. Similarly, user movement of the scroll bars 61 on the graphical view window 62 will change the visible graph contents and this is reflected in the viewing window 62, with the view port rectangle 64 automatically moved accordingly. Dragging the background canvas of the main graphical view has the same effect. FIG. 11 shows an example view 70, wherein as the view port 64 is moved, the displayed portion of the graph 45 in the graphical view window 42 changes correspondingly.

Keeping History of Previous Graph Views in a Browser Environment

In a browser environment, users are familiar with clicking the Back button to return to the previous page of data which was generated as the result of making a HTTP request to a server, and the entire page is fetched and displayed. For web pages using AJAX style technology, typically only those elements of the page that need refreshing are requested from the server asynchronously, and the relevant parts of the screen updated, without redrawing the entire page. The browser address does not change.

In the context of an embodiment of the invention, the user reaches a page which contains the object graph as well as related control elements, such as the viewing window 62, action list 56, and certain filter controls such as a view port 64. After viewing a graph 45, the user may decide to view another graph by starting at another object visible in the graph 45. The user can do so by choosing a Re-focus Graph action in the list of available actions 56, causing an asynchronous request at the server application, which in turn returns updated graph data.

The rendering function of the browser client then uses the updated graph data to render only the content of the graphical view window 42 (all other controls remain on the screen and are not refreshed). As such, less graph data need be sent from the server application to the client over the communication link, and reducing user wait time for screen updates.

The rendering function maintains a graph navigation history which records the origin object for previous graphs, and their various display settings. FIG. 12 shows an example navigation history 75. The display settings may include, e.g., graph depth and filter settings. At any point, the user can now select a link 76 in the graph navigation history 75 to have the graph redrawn by the rendering function from that origin using the original settings.

Reducing Graph Size

A preferred embodiment involves reducing the graph size by depth culling of the graph to reduce graph view complexity and network load between the client and server modules in a registry store computing environment. A preferred embodiment involves the display of multiple relationships between objects stored in a shared registry application. This particular registry stores business service artifacts and maintains relationships between those artifacts, whether they are derived from published documents or created by users of the registry. Relationships can exist between any types of object and to any level of cardinality (from zero to unlimited relationships).

Objects can be connected to several other objects, and those objects in turn can be connected to yet more objects. After just a few levels of objects away from the root object, the total number of objects to calculate a graph for at the server, send to the client to display, and then render, can quickly become large enough to make the calculation time long, and the network traffic high, negatively impacting the response time to the client. The more objects to be drawn and presented to the user, the more the complexity of the corresponding graph, and the lesser the user ability to understand the graph contents.

In addition, the client graph drawing capabilities may be limited by the number of objects to be drawn, with every graphical element, such as a connection line, icon, text label adding to the number of objects to draw. This limit in the client may be experienced by the user as longer waiting times or catastrophic failure of the browser client.

This effect can be diminished by controlling the type and number of data structures sent between the server and client, limiting the time allowed for the graph rendering function to execute, and limiting the number of labels given to objects in the rendered graph. Since the number of objects to draw may grow and exceed the capabilities of the client, the invention further provides controls in the browser client for the user to control graph fetching depth at the server module. This affects how many objects are traversed in the server module, when collecting objects to be added to the graph data structure. Alternative control mode options include graph depth display control information such as:

-   -   Unlimited depth—This control mode allows the server application         in the server module to keep traversing all the relationships in         the hierarchy of objects starting at the root object until there         are no more relationships to follow. This results in the data         graph containing the most accurate representation of the object         graph in the registry. In a highly populated registry where         there exist deep object hierarchies, this option may return         large data structures to the client and exceed the capabilities         of the client.     -   User choice of a precise depth—This control mode allows the user         to select the depth (i.e., number of levels) the server         application traverses relationships from the root object. In a         preferred embodiment, the user is presented with fixed level         depths of e.g. 1, 2, 3 or 4 (or any number). This reduces the         number of objects the server application processes when         retrieving objects, improves the graph creating and graph layout         processing time at the server application, reduces the size of         data sent to the client, and reduces the number of objects that         the client renders in the graph view on the user interface. As         such, system response delay is reduced by faster graph drawing         time. This control mode is useful when the user desires to focus         on a limited number of objects centered around a current root         object in the graph view.     -   Automatic depth—This control mode specifies that the server         application performs a breadth-first traversal of the object         graph in the registry, retrieving objects until the number of         objects reaches a threshold (the threshold may be configurable         e.g. by the user). In one example, this threshold may represent         the number of objects (determined by empirical means) that a         client such as web browser client can render in a reasonable         time without failing or significant degradation in performance.         The control mode allows the transfer of as much graph data from         the server application as possible without risk of failure or         significant degradation in performance on the part of the         browser client.

The control mode options and the resultant graph view in the preferred embodiment may be represented as follows. FIG. 13 shows an example of a user choice of a precise depth control mode 80A (depth of one) and the resultant graph view 80B which displays representations 46 of actual objects as and representations 46 d of dummy objects. As discussed, objects that have connections to other objects that will not be present in the final graph are connected to a dummy object or node that indicates where a graph truncation occurs. This reduced graph layout is sent by the server module to the client module as graph coordinate data, to be rendered visually by the client as a graph view on a user interface. If the user selects a dummy object or node that indicates there is more data originating from the object attached to the dummy node, the client can request that the additional graph data be retrieved from the server module.

FIG. 14 shows an example of the user choice of a precise depth control mode 81A and the resultant graph view 81B which displays representations 46 of actual objects at a user specified depth, and representations 46 d of dummy objects. In this example the user specified a two level graph depth. FIG. 15 shows another example of the user choice of a precise depth control mode 82A (depth of three levels) and the resultant graph view 82B which displays representations 46 of actual objects at that depth threshold, and representations 46 d of dummy objects. The graph of objects in FIG. 15 may equally be the result of drawing a graph with the depth level set to automatic, where the underlying object limit is arbitrarily set to, e.g., eleven objects. In this example, the server application would identify that the twelfth and subsequent objects to be drawn would exceed this threshold and so creates a dummy node which the client draws as an icon indicating a graph truncation.

Referring to the example graph view 85 in FIG. 16, when the number of levels to traverse has been deliberately limited by specifying the number of levels in the object graph to traverse, or when automatic mode truncates the number of objects retrieved when a certain number of objects have been retrieved, and there exist further relationships from the objects in the deepest layers of objects shown, the further layers are shown as dummy object shapes 46 d. Moving a mouse cursor over one of these shapes 46 d displays a tooltip or popup window 86 which informs the user that additional relationships exist emanating from the object shape 46 d and that if the user wishes to retrieve those relationships the user can click the shape 46 d (or whatever icon or text is used to indicate more relationships are available). This centers the graph view on the clicked object 46 d and retrieves a new graph, with the current depth retrieval settings. The new graph view indicates which object is the new root of the rendered graph by highlighting it (e.g., a bold border).

The above processes are now described in further detail in terms of the operations of the server and the client.

Server Processing

When the server application 14 (FIG. 1) is requested to generate graph coordinates and other information for a graph of a given depth starting from a specified origin (root) object, the server application follows this process to discover and maintain relationships that will end up in the graph:

-   -   Starting with the root object ID, the server graph creation         function 18 (FIG. 1) retrieved that object and creates a graph         node with any properties that are required for display (e.g.,         name, type), and is assigned a unique ID. The graph node is         added to a map of node IDs. The graph node is set as the source         node.     -   The server graph creation function 18 recursively traverses         relationships from that source object to find the next level of         target objects to add to the graph, according to the settings         for the graph passed from the client. The settings determine the         depth of objects to be fetched and the types of relationship to         be followed.     -   When a relationship is traversed, each target object is         retrieved and if a retrieved object ID does not exist in the         node map, the server graph creation function 18 creates a graph         node with any properties required for display, as for the source         node, with a unique ID. If the graph node does already exist it         is retrieved from the node map.     -   The server graph creation function 18 then adds the target graph         nodes to an edge object. An edge object represents one or more         relationships between the source object and the target object.         An edge can represent more than one relationship. It does this         by containing a “relationship vector” object for each type of         relationship connecting the source and target object.     -   After an edge is created between source and target graph nodes,         the target nodes are set as source nodes in turn and their         relationships traversed until the depth limit set by the graph         settings object is reached. If the control mode for graph         fetching set to be automatic depth, then throughout this         traversal of relationships by the server graph creation function         18, the number of objects retrieved so far is incremented by one         for each unique object encountered. When the object count         threshold is reached, no further objects are retrieved. However,         if the deepest level objects retrieved in the set of graph         objects have remaining targets (that have not been retrieved         from the registry), then those graph node objects are set with         an indication that there are more outbound relationships.     -   At this point there is a set of graph node objects and a set of         graph edges. This collection of data is then given to the server         graph processing function 19 to transform into a set of graph         objects with coordinates such that the graph meets readability         constraints, that is, the graph contents are arranged such that         the connection crossings are minimized and connection lengths         are reduced to reduce graph density and complexity. The graph         data is serialized and returned to the client 11 as lightweight         data via the communication link.

Client Processing

The client graph processing function 17 processes the object graph data, scaling the coordinates of objects to match the display area, and the client rendering function 16 renders shapes, icons to represent graph objects and adding text properties. Relationships between objects are drawn as connecting lines 47 between the shapes 46, including dummy object shapes 46 d. Specifically, where an object 46 has a flag set indicating more outbound relationships described above, a line/edge is drawn connecting that object to a shape 46 d in to indicate that further relationships exist and can be further traversed if the user clicks on the shape 46 d. The client rendering function 16 may further provide a visual control (e.g., controls 80A, 81A, 82A, above) which reflects the current graph fetching control modes, depth of graph traversal and other criteria for controlling the content of the graph.

As such the invention provides controls that enable the content of the graph to be managed interactively. The number of objects and edges (connections) to be calculated by the server application is reduced, providing improved response times to client applications. The network load between the client and server is reduced (less graph data is transmitted). The client renders less data so it renders more quickly and is less likely to cause a client error. The user views a less complex graph, making it easier for the user to follow paths of interest and request additional data from the server as needed. The user can quickly switch between different views of the same data at different levels of complexity without need to making a server request.

As is known to those skilled in the art, the aforementioned example architectures described above, according to the invention, can be implemented in many ways, such as program instructions for execution by a processor, as software modules, microcode, as computer program product on computer readable media, as logic circuits, as application specific integrated circuits, as firmware, etc. Further, embodiments of the invention can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment containing both hardware and software elements.

FIG. 17 shows a block diagram of an example architecture of an embodiment of a system 100 configured to perform the processes described above, according to an embodiment of the invention. The system 100 includes one or more client devices 101 connected to one or more server computing systems 130. A server 130 includes a bus 102 or other communication mechanism for communicating information, and a processor (CPU) 104 coupled with the bus 102 for processing information. The server 130 also includes a main memory 106, such as a random access memory (RAM) or other dynamic storage device, coupled to the bus 102 for storing information and instructions to be executed by the processor 104. The main memory 106 also may be used for storing temporary variables or other intermediate information during execution or instructions to be executed by the processor 104. The server computer system 130 further includes a read only memory (ROM) 108 or other static storage device coupled to the bus 102 for storing static information and instructions for the processor 104. A storage device 110, such as a magnetic disk or optical disk, is provided and coupled to the bus 102 for storing information and instructions. The bus 102 may contain, for example, thirty-two address lines for addressing video memory or main memory 106. The bus 102 can also include, for example, a 32-bit data bus for transferring data between and among the components, such as the CPU 104, the main memory 106, video memory and the storage 110. Alternatively, multiplex data/address lines may be used instead of separate data and address lines.

The server 130 may be coupled via the bus 102 to a display 112 for displaying information to a computer user. An input device 114, including alphanumeric and other keys, is coupled to the bus 102 for communicating information and command selections to the processor 104. Another type or user input device comprises cursor control 116, such as a mouse, a trackball, or cursor direction keys for communicating direction information and command selections to the processor 104 and for controlling cursor movement on the display 112.

According to one embodiment of the invention, the functions of the invention are performed by the processor 104 executing one or more sequences of one or more instructions contained in the main memory 106. Such instructions may be read into the main memory 106 from another computer-readable medium, such as the storage device 110. Execution of the sequences of instructions contained in the main memory 106 causes the processor 104 to perform the process steps described herein. One or more processors in a multi-processing arrangement may also be employed to execute the sequences of instructions contained in the main memory 106. In alternative embodiments, hard-wired circuitry may be used in place of or in combination with software instructions to implement the invention. Thus, embodiments of the invention are not limited to any specific combination of hardware circuitry and software.

The terms “computer program medium,” “computer usable medium,” “computer readable medium”, and “computer program product,” are used to generally refer to media such as main memory, secondary memory, removable storage drive, a hard disk installed in hard disk drive, and signals. These computer program products are means for providing software to the computer system. The computer readable medium allows the computer system to read data, instructions, messages or message packets, and other computer readable information from the computer readable medium. The computer readable medium, for example, may include non-volatile memory, such as a floppy disk, ROM, flash memory, disk drive memory, a CD-ROM, and other permanent storage. It is useful, for example, for transporting information, such as data and computer instructions, between computer systems. Furthermore, the computer readable medium may comprise computer readable information in a transitory state medium such as a network link and/or a network interface, including a wired network or a wireless network, that allow a computer to read such computer readable information. Computer programs (also called computer control logic) are stored in main memory and/or secondary memory. Computer programs may also be received via a communications interface. Such computer programs, when executed, enable the computer system to perform the features of the present invention as discussed herein. In particular, the computer programs, when executed, enable the processor multi-core processor to perform the features of the computer system. Accordingly, such computer programs represent controllers of the computer system.

Generally, the term “computer-readable medium” as used herein refers to any medium that participated in providing instructions to the processor 104 for execution. Such a medium may take many forms, including but not limited to, non-volatile media, volatile media, and transmission media. Non-volatile media includes, for example, optical or magnetic disks, such as the storage device 110. Volatile media includes dynamic memory, such as the main memory 106. Transmission media includes coaxial cables, copper wire and fiber optics, including the wires that comprise the bus 102. Transmission media can also take the form of acoustic or light waves, such as those generated during radio wave and infrared data communications.

Common forms of computer-readable media include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, or any other magnetic medium, a CD-ROM, any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, a RAM, a PROM, an EPROM, a FLASH-EPROM, any other memory chip or cartridge, a carrier wave as described hereinafter, or any other medium from which a computer can read.

Various forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to the processor 104 for execution. For example, the instructions may initially be carried on a magnetic disk of a remote computer. The remote computer can load the instructions into its dynamic memory and send the instructions over a telephone line using a modem. A modem local to the server 130 can receive the data on the telephone line and use an infrared transmitter to convert the data to an infrared signal. An infrared detector coupled to the bus 102 can receive the data carried in the infrared signal and place the data on the bus 102. The bus 102 carries the data to the main memory 106, from which the processor 104 retrieves and executes the instructions. The instructions received from the main memory 106 may optionally be stored on the storage device 110 either before or after execution by the processor 104.

The server 130 also includes a communication interface 118 coupled to the bus 102. The communication interface 118 provides a two-way data communication coupling to a network link 120 that is connected to the world wide packet data communication network now commonly referred to as the Internet 128. The Internet 128 uses electrical, electromagnetic or optical signals that carry digital data streams. The signals through the various networks and the signals on the network link 120 and through the communication interface 118, which carry the digital data to and from the server 130, are exemplary forms or carrier waves transporting the information.

In another embodiment of the server 130, interface 118 is connected to a network 122 via a communication link 120. For example, the communication interface 118 may be an integrated services digital network (ISDN) card or a modem to provide a data communication connection to a corresponding type of telephone line, which can comprise part of the network link 120. As another example, the communication interface 118 may be a local area network (LAN) card to provide a data communication connection to a compatible LAN. Wireless links may also be implemented. In any such implementation, the communication interface 118 sends and receives electrical electromagnetic or optical signals that carry digital data streams representing various types of information.

The network link 120 typically provides data communication through one or more networks to other data devices. For example, the network link 120 may provide a connection through the local network 122 to a host computer 124 or to data equipment operated by an Internet Service Provider (ISP) 126. The ISP 126 in turn provides data communication services through the Internet 128. The local network 122 and the Internet 128 both use electrical, electromagnetic or optical signals that carry digital data streams. The signals through the various networks and the signals on the network link 120 and through the communication interface 118, which carry the digital data to and from the server 130, are exemplary forms or carrier waves transporting the information.

The server 130 can send/receive messages and data, including e-mail, program code, through the network, the network link 120 and the communication interface 118. Further, the communication interface 118 can comprise a USB/Tuner and the network link 120 may be an antenna or cable for connecting the server 130 to a cable provider, satellite provider or other terrestrial transmission system for receiving messages, data and program code from another source.

The example versions of the invention described herein are implemented as logical operations in a distributed processing system such as the system 100 including the servers 130. The logical operations of the present invention can be implemented as a sequence of steps executing in the server 130, and as interconnected machine modules within the system 100. The implementation is a matter of choice and can depend on performance of the system 100 implementing the invention. As such, the logical operations constituting said example versions of the invention are referred to for e.g. as operations, steps or modules.

Similar to a server 130 described above, a client device 101 can include a processor, memory, storage device, display, input device and communication interface (e.g., e-mail interface) for connecting the client device to the Internet 128, the ISP 126, or LAN 122, for communication with the servers 130.

The system 100 can further include computers (e.g., personal computers, computing nodes) 105 operating the same manner as client devices 101, wherein a user can utilize one or more computers 105 to manage data in the server 130.

Those skilled in the art will appreciate that various adaptations and modifications of the just-described preferred embodiments can be configured without departing from the scope and spirit of the invention. Therefore, it is to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described herein. 

1. A method for generating a graph view on a user interface in a computing environment, comprising: at a server, generating coordinate data for a graph representing multiply connected objects; transmitting the coordinate data to a client as lightweight object data; and at the client, based on the lightweight object data rendering an interactive dynamic graph view on a user interface; wherein the rendered graph view includes representations of a plurality of the multiply connected objects selected by depth culling the graph according to graph depth display control information.
 2. The method of claim 1 wherein the graph depth display control information includes a threshold for controlling the amount of graph data sent to a client form the server.
 3. The method of claim 1 wherein the graph view includes visual elements connected by edges, such that the visual elements represent the objects and the edges represent relationships between the objects, and the graph depth display control information includes a threshold for controlling the amount of graph data sent to a client form the server; the method further including examining relationships in the graph of objects and counting the number of objects added to the graph, such that when the number of objects reaches said threshold, no additional objects are added to the graph.
 4. The method of claim 3 further including: detecting objects that have connections to other objects beyond said threshold, and representing said objects beyond said threshold by a specialized representation indicating a graph truncation.
 5. The method of claim 4 further including: upon receiving user selection of a specialized representation, request additional graph data from the server and rendering the additional graph data at the client.
 6. The method of claim 4 wherein the graph depth control information includes: unlimited depth, wherein the server traverses all the relationships in the hierarchy of objects starting at a root object until there are no more relationships to follow; or automatic depth, wherein the server performs a breadth-first traversal of the object graph data, retrieving objects until the number of objects reaches a threshold.
 7. The method of claim 6 further including receiving the graph depth control information from a user.
 8. The method of claim 1 wherein the computing environment comprises a service-oriented architecture and the data source comprises a service registry, the client comprises a web browser on a thin client computing module, the server comprises a server application on a server computing module, wherein the client module and the server module may be connected via a communication link.
 9. A computer program product for generating a graph view on a user interface in a computing environment, comprising a computer usable medium including a computer readable program including program instructions, wherein the computer readable program when executed on a computer system causes the computer system to: at a server, generate coordinate data for a graph representing multiply connected objects, and transmit the coordinate data to a client as lightweight object data; and at the client, based on the lightweight object data rendering an interactive dynamic graph view on a user interface; wherein the rendered graph view includes representations of a plurality of the multiply connected objects selected by depth culling the graph according to graph depth display control information.
 10. The computer program product of claim 9 wherein the graph depth display control information includes a threshold for controlling the amount of graph data sent to a client from the server.
 11. The computer program product of claim 9 wherein the graph view includes visual elements connected by edges, such that the visual elements represent the objects and the edges represent relationships between the objects, and the graph depth display control information includes a threshold for controlling the amount of graph data sent to a client form the server; and the computer program product further including instructions for examining relationships in the graph of objects and counting the number of objects added to the graph, such that when the number of objects reaches said threshold, no additional objects are added to the graph.
 12. The computer program product of claim 11 further including instructions for detecting objects that have connections to other objects beyond said threshold, and representing said objects beyond said threshold by a specialized representation indicating a graph truncation.
 13. The computer program product of claim 12 further including instructions for: upon receiving user selection of a specialized representation, request additional graph data from the server and rendering the additional graph data at the client.
 14. The computer program product of claim 12 wherein the graph depth control information includes: unlimited depth, wherein the computer program product further includes instructions for traversing all the relationships in the hierarchy of objects starting at a root object until there are no more relationships to follow; or automatic depth, wherein the computer program product further includes instructions for performing a breadth-first traversal of the object graph data, retrieving objects until the number of objects reaches a threshold.
 15. The computer program product of claim 14 further including instructions for receiving the graph depth control information from a user.
 16. The computer program product of claim 9 wherein the computing environment comprises a service-oriented architecture and the data source comprises a service registry, the client comprises a web browser on a thin client computing module, the server comprises a server application on a server computing module, wherein the client module and the server module may be connected via a communication link.
 17. A system for generating a graph view on a user interface in a computing environment, comprising: a server function configured for generating coordinate data for a graph representing multiply connected objects, and transmitting the coordinate data to a client as lightweight object data; and a client rendering function configured for rendering an interactive dynamic graph view of the multiply connected objects on a user interface at the client, based on the lightweight object data; wherein the rendered graph view includes representations of a plurality of the multiply connected objects selected by depth culling the graph according to graph depth display control information.
 18. The system of claim 17 wherein the graph depth display control information includes a threshold for controlling the amount of graph data sent to a client from the server.
 19. The system of claim 17 wherein the graph view includes visual elements connected by edges, such that the visual elements represent the objects and the edges represent relationships between the objects, and the graph depth display control information includes a threshold for controlling the amount of graph data sent to a client form the server; the server function further configured for examining relationships in the graph of objects and counting the number of objects added to the graph, such that when the number of objects reaches said threshold, no additional objects are added to the graph.
 20. The system of claim 17 wherein: the graph depth control information includes: unlimited depth, wherein the server traverses all the relationships in the hierarchy of objects starting at a root object until there are no more relationships to follow; and automatic depth, wherein the server performs a breadth-first traversal of the object graph data, retrieving objects until the number of objects reaches a threshold; the server function is further configured for detecting objects that have connections to other objects beyond said threshold, and the client function is further configured for representing said objects beyond said threshold by a specialized representation indicating a graph truncation; the client function is further configured such that, upon receiving user selection of a specialized representation, the client function requests additional graph data from the server and rendering the additional graph data at the client; and the computing environment comprises a service-oriented architecture and the data source comprises a service registry, the client comprises a web browser on a thin client computing module, the server comprises a server application on a server computing module, wherein the client module and the server module may be connected via a communication link. 